基于表面等离子体激元的金属透镜聚焦研究

表面等离子体激元(Surface plasmon polaritons,SPPs)是由金属表面的自由电子随入射光的光子集体共振,产生在金属-介质界面的一种非辐射表面电磁模式。其具有亚波长约束、近场增强和异常色散等特点使得在亚波长尺度的金属结构中对光场实现局域化和导波成为可能,这些聚焦结构在纳米光子集成、光密集存储、生物技术、超分辨成像等领域具有巨大的应用前景。文章在总结表面等离子体激元的理论和实验的基础上,对亚波长金属透镜的聚焦深入分析,优化结构使其在纳米尺度内能够对光场进行有效的调控和聚焦。

Surface plasmon polaritons(SPPs)are nonradiative surface electromagnetic mode generated by the collective resonance of free electrons on a metal surface with photons of incident light at the metal-medium interface.The characteristics of sub-wavelength confinement,near-field enhancement and anomalous dispersion make it possible to localize and guide the light field in the sub-wave-length scale metal structure.These focused structures have great potential applications in the fields of nano-photonic integration,opti-cal dense storage,biotechnology,super-resolution imaging and so on.On the basis of summing up the theory and experiment of sur-face plasmon,the focus of subwavelength metal lens is analyzed,and the structure is optimized,so that it can effectively control and focus the light field in the nanometer scale.